U.S. patent application number 16/050115 was filed with the patent office on 2019-02-07 for pressure trip unit for an electrical switch and electrical switch with such a pressure trip unit.
This patent application is currently assigned to Siemens Aktiengesellschaft. The applicant listed for this patent is Siemens Aktiengesellschaft. Invention is credited to Oliver ANDERSEN, Pawel BIEDUNKIEWICZ, Joerg-uwe DAHL, Erhard DEYLITZ.
Application Number | 20190043679 16/050115 |
Document ID | / |
Family ID | 62985979 |
Filed Date | 2019-02-07 |
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United States Patent
Application |
20190043679 |
Kind Code |
A1 |
ANDERSEN; Oliver ; et
al. |
February 7, 2019 |
PRESSURE TRIP UNIT FOR AN ELECTRICAL SWITCH AND ELECTRICAL SWITCH
WITH SUCH A PRESSURE TRIP UNIT
Abstract
A pressure trip unit for an electrical switch, including an
actuating element and at least one flow channel per electrical
pole, is disclosed. In an embodiment, the at least one pole of the
electrical switch includes at least two switching contacts for
making or disconnecting a flow path. The switching contacts of the
at least one pole of the electrical switch are disconnectable via
the actuating element which can respond to a pressure generated in
a disconnection zone of the, in each case, two switching contacts
by an electric arc drawn in the event of an electrodynamic recoil
of the switching contacts. Further, the disconnection zone is
connectable to the actuating element via the flow channel, the at
least one flow channel including a nonreturn valve to permit a flow
only from the disconnection zone in the direction of the actuating
element.
Inventors: |
ANDERSEN; Oliver; (Berlin,
DE) ; BIEDUNKIEWICZ; Pawel; (Berlin, DE) ;
DAHL; Joerg-uwe; (Werder, DE) ; DEYLITZ; Erhard;
(Berlin, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Siemens Aktiengesellschaft |
Munich |
|
DE |
|
|
Assignee: |
Siemens Aktiengesellschaft
Munich
DE
|
Family ID: |
62985979 |
Appl. No.: |
16/050115 |
Filed: |
July 31, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01H 33/53 20130101;
H01H 2071/2427 20130101; H01H 2077/025 20130101; H01H 33/82
20130101; H01H 33/83 20130101; H01H 33/022 20130101; H01H 9/342
20130101; H01H 33/42 20130101; H01H 2009/343 20130101 |
International
Class: |
H01H 33/42 20060101
H01H033/42; H01H 33/82 20060101 H01H033/82; H01H 33/53 20060101
H01H033/53 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 1, 2017 |
DE |
102017213238.8 |
Jul 18, 2018 |
DE |
102018211995.3 |
Claims
1. A pressure trip unit for an electrical switch, comprising: an
actuating element; and at least one flow channel, each at least one
flow channel respectively corresponding to each of at least one
electrical pole of the electrical switch, wherein each at least one
pole of the electrical switch includes at least two switching
contacts for making or disconnecting a flow path, wherein the at
least two switching contacts of each at least one pole of the
electrical switch are disconnectable via the actuating element, the
actuating element being configured to respond to a pressure
generated in a disconnection zone of each respective switching
contact of the at least two switching contacts by an electric arc
drawn in an event of an electrodynamic recoil of each of the
switching contacts, and wherein the disconnection zone is
connectable to the actuating element via the at least one flow
channel, the at least one flow channel including a nonreturn valve
to permit a flow only from the disconnection zone in a direction of
the actuating element.
2. The pressure trip unit of claim 1, wherein the electrical switch
is a multi-pole electrical switch, wherein the at least one pole of
the multi-pole electrical switch includes a plurality of poles, and
wherein nonreturn valves of the multi-pole electrical switch are
configured to prevent a flow from one disconnection zone to another
disconnection zone of the plurality of poles of the electrical
switch.
3. The pressure trip unit of claim 2, further comprising: a common
collecting chamber, arranged between the nonreturn valves and the
actuating element, wherein the common collecting chamber is
arranged in terms of flow at an output of the nonreturn valves.
4. The pressure trip unit of claim 1, wherein the nonreturn valves
include a tongue, the tongue, in an inoperative state, covering the
at least one flow channel and the tongue, in an event of pressure
in an associated disconnection zone, being configured to open up
the at least one flow channel.
5. The pressure trip unit of claim 4, wherein the tongue is
manufactured from aramid.
6. The pressure trip unit of claim 4, wherein a response behavior
of the nonreturn valves is set by a material thickness of the
tongue or by a rigidity of the material.
7. The pressure trip unit of claim 4, further comprising: a
housing, including a first housing part and a second housing part,
the tongue being held between the first housing part and the second
housing part.
8. The pressure trip unit of claim 7, wherein a response behavior
of the nonreturn valves is set by at least one of an angle and a
bending radius of a holding zone of the tongue of the first housing
part and the second housing part.
9. The pressure trip unit of claim 1, wherein the actuating element
is designed as a tappet.
10. The pressure trip unit of claim 9, wherein the tappet is held
in an inoperative position by a spring and is actuatable, in an
event of pressure, counter to a spring force of the spring.
11. The pressure trip of claim 1, wherein the pressure trip unit is
constructed modularly from at least two valve elements, each
respective valve element of the at least two valve elements
including a respective nonreturn valve and a respective flow
channel; and a tripping element including the actuating element,
the at least two valve elements and the tripping element being
designed to be pluggable together.
12. The pressure trip unit of claim 11, wherein the pressure trip
unit comprises closing elements and connecting elements to connect
or close at least one of the at least two valve elements and the
tripping element to one another.
13. An electrical switch, comprising: a plurality of poles; and the
pressure trip unit of claim 1, wherein each of the plurality of
poles of the electrical switch comprise at least two switching
contacts to make a flow path or disconnect a flow path, wherein the
at least two switching contacts of the plurality of poles of the
electrical switch are disconnected via the actuating element
responding to a pressure generated in a disconnection zone of at
least one of the at least two switching contacts by an electric arc
drawn in an event of an electrodynamic recoil of the at least two
switching contacts, wherein the at least one flow channel of the
pressure trip unit includes at least two flow channels, each
respective flow channel of the at least two flow channels
corresponding to each respective pole of the plurality of
electrical poles of the electrical switch, and wherein the
disconnection zones of the at least two switching contacts are
connected to the actuating element via the at least two flow
channels.
14. The electrical switch of claim 13, wherein the electrical
switch comprises two or three electrical poles, and wherein the
pressure trip unit comprises three or four flow channels.
15. The electrical switch of claim 13, wherein the electrical
switch further comprises a protective barrier to prevent direct
transport of particles from the disconnection zone to the pressure
trip unit.
16. The pressure trip unit of claim 5, wherein a response behavior
of the nonreturn valves is set by a material thickness of the
tongue or by a rigidity of the material.
17. The pressure trip unit of claim 2, wherein the nonreturn valves
include a tongue, the tongue, in an inoperative state, covering the
at least one flow channel and the tongue, in an event of pressure
in an associated disconnection zone, being configured to open up
the at least one flow channel.
18. The pressure trip unit of claim 2, wherein the actuating
element is designed as a tappet.
19. The pressure trip of claim 2, wherein the pressure trip unit is
constructed modularly from at least two valve elements, each
respective valve element of the at least two valve elements
including a respective nonreturn valve and a respective flow
channel; and a tripping element including the actuating element,
the at least two valve elements and the tripping element being
designed to be pluggable together.
20. An electrical switch, comprising: a plurality of poles; and the
pressure trip unit of claim 2, wherein each of the plurality of
poles of the electrical switch comprise at least two switching
contacts to make a flow path or disconnect a flow path, wherein the
at least two switching contacts of the plurality of poles of the
electrical switch are disconnected via the actuating element
responding to a pressure generated in a disconnection zone of at
least one of the at least two switching contacts by an electric arc
drawn in an event of an electrodynamic recoil of the at least two
switching contacts, wherein the at least one flow channel of the
pressure trip unit includes at least two flow channels, each
respective flow channel of the at least two flow channels
corresponding to each respective pole of the plurality of
electrical poles of the electrical switch, and wherein the
disconnection zones of the at least two switching contacts are
connected to the actuating element via the at least two flow
channels.
Description
PRIORITY STATEMENT
[0001] The present application hereby claims priority under 35
U.S.C. .sctn.119 to German patent applications numbers DE
102017213238.8 filed Aug. 1, 2017 and DE 102018211995.3 filed Jul.
18, 2018, the entire contents of each of which are hereby
incorporated herein by reference.
FIELD
[0002] At least one embodiment of the invention generally relates
to a pressure trip unit for an electrical switch, and/or to an
electrical switch comprising such a pressure trip unit.
BACKGROUND
[0003] Typically, current-limiting switchgears, in particular
current-limiting circuit breakers, for example in the form of MCCBs
(Molded Case Circuit Breakers), are used in extensively branched
power distribution networks. It is customary to conduct selective
staggering with a minimum nominal current distance between the
switchgears involved. Each branching plane can be protected here
against overloads and short circuits that occur by a switchgear
which is appropriately dimensioned depending on the connected
consumers.
[0004] For example, a switchgear which is arranged closest to a
consumer and which is often referred to as a consumer-close or
downstream switchgear, is configured for the lowest nominal
current. If a short circuit current then flows both through the
consumer-close switchgear and through a switchgear which is
arranged above the consumer-near switchgear in the hierarchy of the
power distribution network and is often referred to as a
consumer-remote or upstream switchgear, only the consumer-near
switchgear is intended to switch off. In other words, in the event
of a malfunction (short circuit), only the switchgear which is
closest to the event is intended to break the current flow.
[0005] Upon opening, the switching contact pairs of the
consumer-close and of the consumer-remote switchgear draw an
electric arc, wherein the opening width of the switching contact
pairs and also the electric arc energy are higher in the case of
the consumer-close switchgear because of the lower mass moment of
inertia of its movable current path including the switching
contact. This opening, which, under some circumstances, is only a
single-pole opening, has to be followed by an all-pole switching
off of the consumer-close switchgear. The consumer-remote
switchgear must not switch off so as not to disconnect further
consumers from the power distribution network. However, the
consumer-remote switchgear must act in an assisting manner by brief
raising of the switching contacts, i.e. must contribute, for
example, to the switching off of the consumer-close switchgear by
limiting the current.
[0006] Switchgears which act in such a staggered manner in power
distribution networks behave selectively. In order to achieve this
selectivity, the switchgears lying closest to the malfunction have
to break the current paths of all of the switching poles more
rapidly than the switchgears arranged thereabove.
[0007] DE 691 10 540 T2 and DE 692 17 441 T2 each disclose
electrical switching arrangements in the form of circuit breakers
with insulating material housings, which, per switching pole,
comprise two switching contacts which are pressed resiliently
against each other in the switching-on position of the circuit
breaker. The switching contacts can be disconnected by the action
of electrodynamic recoil forces if the current flowing through the
switching contacts exceeds a certain threshold value, in order
thereby to bring about a limiting of the current mentioned.
[0008] The circuit breaker disclosed in the documents comprises an
overload and/or short circuit detection element for acting upon a
switching off mechanism which brings about the automatic switching
off of the circuit breaker in the event of a fault. Furthermore,
the circuit breaker disclosed in the documents comprises an
actuating element which responds to a positive pressure generated
in the disconnection zone of the switching contacts by way of an
electric arc drawn in the event of an electrodynamic recoil of the
switching contacts, in order to actuate the switching off mechanism
of the circuit breaker.
[0009] The actuating element disclosed in the documents is a
gas-tight unit which is connected exclusively to the disconnection
zone of the switching contacts and comprises a movable element, for
example a piston or a membrane, with a limited control stroke. The
movable element is acted upon firstly with the positive pressure
and secondly by a restoring device with adapted active force. The
displacement of the movable element brings about the tripping of
the switching off mechanism of the circuit breaker, wherein the
restoring device with adapted active force is dimensioned such that
an undesirable tripping in the event of a simple overload or a
response of a downstream, current-limiting circuit breaker is
prevented.
[0010] Further pressure trip units are likewise disclosed in the
documents DE 10 2009 015 126 A1 and DE 10 2011 077 359 A1.
SUMMARY
[0011] At least one embodiment of the invention specifies an
alternative pressure trip unit.
[0012] At least one embodiment of the invention is directed to a
pressure trip unit. Advantageous refinements of the pressure trip
unit are specified in the embodiments. At least one embodiment of
the invention is directed to an electric switch. Advantageous
refinements are specified in the embodiments.
[0013] The pressure trip unit for an electrical switch of at least
one embodiment comprises an actuating element and at least one flow
channel per electrical pole, wherein the at least one pole of the
electrical switch comprises at least two switching contacts for
making or disconnecting a flow path, wherein the switching contacts
of the at least one pole of the electrical switch are
disconnectable by way of the actuating element which can respond to
a pressure which is generated in a disconnection zone of the in
each case two switching contacts by an electric arc drawn in the
event of an electrodynamic recoil of the switching contacts, and
wherein the disconnection zone is connectable to the actuating
element via the flow channel, wherein the at least one flow channel
comprises a nonreturn valve which permits a flow only from the
disconnection zone in the direction of the actuating element.
[0014] The electrical switch comprising a plurality of poles of at
least one embodiment comprises a pressure trip unit according to at
least one embodiment of the invention, wherein the plurality of
poles of the electrical switch each comprise at least two switching
contacts for making or disconnecting a flow path, wherein the
switching contacts of the plurality of poles of the electrical
switch are disconnected by way of the actuating element which
responds to a pressure which is generated in a disconnection zone
of the respective two switching contacts by an electric arc drawn
in the event of an electrodynamic recoil of the switching contacts,
and wherein the disconnection zones are connected to the actuating
element via the flow channels.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above-described properties, features and advantages of
this invention, and the manner in which they are achieved, will
become clearer and more clearly comprehensible in conjunction with
the description below of the example embodiments which will be
explained in more detail in conjunction with the figures.
[0016] In the figures:
[0017] FIG. 1 shows a pressure trip unit with a first housing part
and a second housing part;
[0018] FIG. 2 shows a nonreturn valve with a tongue;
[0019] FIG. 3 shows an electrical switch with a pressure trip
unit;
[0020] FIG. 4 shows an electrical switch with a plurality of poles
and pressure trip unit;
[0021] FIG. 5 shows a modular pressure trip unit;
[0022] FIG. 6A and 6B show an electric switch with a pressure trip
unit and a protective barrier;
[0023] FIG. 7 shows a flow profile in the electrical switch with a
pressure trip unit and a protective barrier;
[0024] FIGS. 8A and 8B show an electrical switch with a pressure
trip unit and an alternative protective barrier;
[0025] FIG. 9 shows a flow profile in the electrical switch with a
pressure trip unit and an alternative protective barrier;
[0026] FIGS. 10A and 10B show an electrical switch with a pressure
trip unit and a further protective barrier.
DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS
[0027] In the following, embodiments of the invention are described
in detail with reference to the accompanying drawings. It is to be
understood that the following description of the embodiments is
given only for the purpose of illustration and is not to be taken
in a limiting sense. It should be noted that the drawings are to be
regarded as being schematic representations only, and elements in
the drawings are not necessarily to scale with each other. Rather,
the representation of the various elements is chosen such that
their function and general purpose become apparent to a person
skilled in the art.
[0028] The drawings are to be regarded as being schematic
representations and elements illustrated in the drawings are not
necessarily shown to scale. Rather, the various elements are
represented such that their function and general purpose become
apparent to a person skilled in the art. Any connection or coupling
between functional blocks, devices, components, or other physical
or functional units shown in the drawings or described herein may
also be implemented by an indirect connection or coupling. A
coupling between components may also be established over a wireless
connection. Functional blocks may be implemented in hardware,
firmware, software, or a combination thereof.
[0029] Various example embodiments will now be described more fully
with reference to the accompanying drawings in which only some
example embodiments are shown. Specific structural and functional
details disclosed herein are merely representative for purposes of
describing example embodiments. Example embodiments, however, may
be embodied in various different forms, and should not be construed
as being limited to only the illustrated embodiments. Rather, the
illustrated embodiments are provided as examples so that this
disclosure will be thorough and complete, and will fully convey the
concepts of this disclosure to those skilled in the art.
Accordingly, known processes, elements, and techniques, may not be
described with respect to some example embodiments. Unless
otherwise noted, like reference characters denote like elements
throughout the attached drawings and written description, and thus
descriptions will not be repeated. The present invention, however,
may be embodied in many alternate forms and should not be construed
as limited to only the example embodiments set forth herein.
[0030] It will be understood that, although the terms first,
second, etc. may be used herein to describe various elements,
components, regions, layers, and/or sections, these elements,
components, regions, layers, and/or sections, should not be limited
by these terms. These terms are only used to distinguish one
element from another. For example, a first element could be termed
a second element, and, similarly, a second element could be termed
a first element, without departing from the scope of example
embodiments of the present invention. As used herein, the term
"and/or," includes any and all combinations of one or more of the
associated listed items. The phrase "at least one of" has the same
meaning as "and/or".
[0031] Spatially relative terms, such as "beneath," "below,"
"lower," "under," "above," "upper," and the like, may be used
herein for ease of description to describe one element or feature's
relationship to another element(s) or feature(s) as illustrated in
the figures. It will be understood that the spatially relative
terms are intended to encompass different orientations of the
device in use or operation in addition to the orientation depicted
in the figures. For example, if the device in the figures is turned
over, elements described as "below," "beneath," or "under," other
elements or features would then be oriented "above" the other
elements or features. Thus, the example terms "below" and "under"
may encompass both an orientation of above and below. The device
may be otherwise oriented (rotated 90 degrees or at other
orientations) and the spatially relative descriptors used herein
interpreted accordingly. In addition, when an element is referred
to as being "between" two elements, the element may be the only
element between the two elements, or one or more other intervening
elements may be present.
[0032] Spatial and functional relationships between elements (for
example, between modules) are described using various terms,
including "connected," "engaged," "interfaced," and "coupled."
Unless explicitly described as being "direct," when a relationship
between first and second elements is described in the above
disclosure, that relationship encompasses a direct relationship
where no other intervening elements are present between the first
and second elements, and also an indirect relationship where one or
more intervening elements are present (either spatially or
functionally) between the first and second elements. In contrast,
when an element is referred to as being "directly" connected,
engaged, interfaced, or coupled to another element, there are no
intervening elements present. Other words used to describe the
relationship between elements should be interpreted in a like
fashion (e.g., "between," versus "directly between," "adjacent,"
versus "directly adjacent," etc.).
[0033] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
example embodiments of the invention. As used herein, the singular
forms "a," "an," and "the," are intended to include the plural
forms as well, unless the context clearly indicates otherwise. As
used herein, the terms "and/or" and "at least one of" include any
and all combinations of one or more of the associated listed items.
It will be further understood that the terms "comprises,"
"comprising," "includes," and/or "including," when used herein,
specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items. Expressions such as "at
least one of," when preceding a list of elements, modify the entire
list of elements and do not modify the individual elements of the
list. Also, the term "exemplary" is intended to refer to an example
or illustration.
[0034] When an element is referred to as being "on," "connected
to," "coupled to," or "adjacent to," another element, the element
may be directly on, connected to, coupled to, or adjacent to, the
other element, or one or more other intervening elements may be
present. In contrast, when an element is referred to as being
"directly on," "directly connected to," "directly coupled to," or
"immediately adjacent to," another element there are no intervening
elements present.
[0035] It should also be noted that in some alternative
implementations, the functions/acts noted may occur out of the
order noted in the figures. For example, two figures shown in
succession may in fact be executed substantially concurrently or
may sometimes be executed in the reverse order, depending upon the
functionality/acts involved.
[0036] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which example
embodiments belong. It will be further understood that terms, e.g.,
those defined in commonly used dictionaries, should be interpreted
as having a meaning that is consistent with their meaning in the
context of the relevant art and will not be interpreted in an
idealized or overly formal sense unless expressly so defined
herein.
[0037] Before discussing example embodiments in more detail, it is
noted that some example embodiments may be described with reference
to acts and symbolic representations of operations (e.g., in the
form of flow charts, flow diagrams, data flow diagrams, structure
diagrams, block diagrams, etc.) that may be implemented in
conjunction with units and/or devices discussed in more detail
below. Although discussed in a particularly manner, a function or
operation specified in a specific block may be performed
differently from the flow specified in a flowchart, flow diagram,
etc. For example, functions or operations illustrated as being
performed serially in two consecutive blocks may actually be
performed simultaneously, or in some cases be performed in reverse
order. Although the flowcharts describe the operations as
sequential processes, many of the operations may be performed in
parallel, concurrently or simultaneously. In addition, the order of
operations may be re-arranged. The processes may be terminated when
their operations are completed, but may also have additional steps
not included in the figure. The processes may correspond to
methods, functions, procedures, subroutines, subprograms, etc.
[0038] Specific structural and functional details disclosed herein
are merely representative for purposes of describing example
embodiments of the present invention. This invention may, however,
be embodied in many alternate forms and should not be construed as
limited to only the embodiments set forth herein.
[0039] Although described with reference to specific examples and
drawings, modifications, additions and substitutions of example
embodiments may be variously made according to the description by
those of ordinary skill in the art. For example, the described
techniques may be performed in an order different with that of the
methods described, and/or components such as the described system,
architecture, devices, circuit, and the like, may be connected or
combined to be different from the above-described methods, or
results may be appropriately achieved by other components or
equivalents.
[0040] The pressure trip unit for an electrical switch of at least
one embodiment comprises an actuating element and at least one flow
channel per electrical pole, wherein the at least one pole of the
electrical switch comprises at least two switching contacts for
making or disconnecting a flow path, wherein the switching contacts
of the at least one pole of the electrical switch are
disconnectable by way of the actuating element which can respond to
a pressure which is generated in a disconnection zone of the in
each case two switching contacts by an electric arc drawn in the
event of an electrodynamic recoil of the switching contacts, and
wherein the disconnection zone is connectable to the actuating
element via the flow channel, wherein the at least one flow channel
comprises a nonreturn valve which permits a flow only from the
disconnection zone in the direction of the actuating element.
[0041] The pressure trip unit according to an embodiment of the
invention is optimized for rapid tripping. In terms of its design,
it can be constructed compact so that the paths for the compressed
air are kept short, which can ensure more rapid tripping. The
pressure trip unit according to an embodiment of the invention can
be designed as an assembly with integrated nonreturn valves at the
interface with the pole cassette.
[0042] In one refined embodiment, the nonreturn valves prevent a
flow from one disconnection zone to another disconnection zone of
the poles of a multi-pole electrical switch.
[0043] In a further refined embodiment, the pressure trip unit
comprises a common collecting chamber which is arranged between the
respective nonreturn valves and the actuating element, wherein the
common collecting chamber is arranged in terms of flow at the
output of the respective nonreturn valves.
[0044] In a further refined embodiment, the nonreturn valve
comprises a tongue which, in the inoperative state, covers the flow
channel and, in the event of pressure in the associated
disconnection zone, opens up the flow channel. The tongue can be
manufactured, for example, from aramid. It is advantageous here
that aramid is particularly heat-resistant.
[0045] In a further refined embodiment, the response behavior of
the nonreturn valve is set by the material thickness of the tongue
or by the rigidity of the material.
[0046] In a further refined embodiment, the pressure trip unit
comprises a housing consisting of a first housing part and a second
housing part, in which the tongue is held between the first housing
part and the second housing part.
[0047] In one refined embodiment, the response behavior of the
nonreturn valve is set by the angle (.alpha.) and/or the bending
radius of the holding zone of the tongue of the first housing part
and the second housing part.
[0048] In a further refined embodiment, the actuating element is
designed as a tappet. The tappet can be held in an inoperative
position by a spring and is actuated in the event of pressure
counter to the spring force of the spring.
[0049] In one refined embodiment, the pressure trip unit is
constructed modularly from at least two valve elements having a
respective nonreturn valve and a respective flow channel and also a
tripping element with the actuating element, wherein the at least
two valve elements and the tripping element are to be able to be
plugged together.
[0050] In a further refined embodiment, the pressure trip unit
comprises closing elements and connecting elements which connect
the at least two valve elements and/or the tripping element to one
another or close same.
[0051] The electrical switch comprising a plurality of poles of at
least one embodiment comprises a pressure trip unit according to at
least one embodiment of the invention, wherein the plurality of
poles of the electrical switch each comprise at least two switching
contacts for making or disconnecting a flow path, wherein the
switching contacts of the plurality of poles of the electrical
switch are disconnected by way of the actuating element which
responds to a pressure which is generated in a disconnection zone
of the respective two switching contacts by an electric arc drawn
in the event of an electrodynamic recoil of the switching contacts,
and wherein the disconnection zones are connected to the actuating
element via the flow channels.
[0052] In one refined embodiment, the electrical switch comprises
one, two or three electrical poles, and the pressure trip unit
comprises three or four flow channels.
[0053] In a further refined embodiment, the electrical switch
furthermore comprises a protective barrier which prevents direct
transport of particles from the disconnection zone to the pressure
trip unit.
[0054] FIG. 1 illustrates a pressure trip unit 100 according to an
embodiment of the invention for an electrical switch 1000. The
pressure trip unit 100 comprises a housing 190 consisting of a
first housing part 191 and a second housing part 192. Flow channels
151; 152; 153 which interact with, and are connectable to,
disconnection zones 1201; 1202; 1203 of the electrical poles 1101;
1102; 1103 of the electrical switch 1000 are attached to the second
housing part 192.
[0055] The first housing part 191 and the second housing part 192
of the pressure trip unit 100 can be connected by way of laser beam
welding, ultrasonic welding, adhesive bonding or other joining
methods in order to ensure as great a gas tightness as
possible.
[0056] A multi-pole electrical switch 1000 is illustrated in FIG.
4. It comprises a plurality of poles 1101; 1102; 1103 having in
each case at least two switching contacts 1211, 1221; 1212, 1222;
1213, 1223 for making or disconnecting a current path. Electrical
switches 1000 with two switching contacts (for example, a switching
contact pair consisting of a moving contact and a fixed contact)
are called single breaking electrical switches, and, in the event
of more than two switching contacts (for example, a plurality of
switching contact pairs), multiply breaking switches are referred
to. The pressure trip unit 100 according to an embodiment of the
invention is suitable for single breaking and for multiply breaking
electrical switches 1000.
[0057] According to FIG. 4, the multi-pole electrical switch 1000
can comprise, for example, three electrical poles 1101; 1102; 1103.
The switching contacts 1211, 1221; 1212, 1222; 1213, 1223 of the
plurality of poles 1101; 1102; 1103 of the electrical switch 1000
can be disconnected via an actuating element 110 of the pressure
trip unit 100, wherein the actuating element 110 can respond to a
pressure (p) which is generated in a disconnection zone 1201, 1202,
1203 of the respective two switching contacts 1211, 1221; 1212,
1222; 1213, 1223 by an electric arc (LB) drawn in the event of an
electrodynamic recoil of the switching contacts 1211, 1221; 1212,
1222; 1213, 1223. The disconnection zones 1201; 1202; 1203 are
connected to the actuating element 110 via the flow channels 151;
152; 153. This means that the pressure (p) which arises in the
disconnection zones 1201; 1202; 1203 because of the drawn electric
arc (LB) is conducted in terms of flow within the pressure trip
unit 100 to the actuating element 110.
[0058] The pressure trip unit 100 furthermore comprises nonreturn
valves 161; 162; 163, as illustrated, for example, in FIG. 2. The
nonreturn valves 161; 162; 163 are arranged at the respective flow
channels 151; 152; 153 and only permit a flow from the respective
disconnection zones 1201; 102; 1203 in the direction of the
actuating element 110. The nonreturn valves 161; 162; 163
especially serve to prevent a flow being possible from one
disconnection zone 1201; 1202; 1203 to another disconnection zone
1201; 1202; 1203 of the poles 1101; 1102; 1103 of the electrical
switch 100.
[0059] According to FIG. 2, the nonreturn valve 161 comprises a
tongue 181 which, in the inoperative state, covers the flow channel
151, as is illustrated in FIG. 2. In the event of a pressure (p) in
the disconnection zone 1201 assigned to the flow channel 151, the
tongue 181 opens up the flow channel 151 and a flow downward in
accordance with FIG. 2 is made possible. Tongue 181 is then located
in the position illustrated by dashed lines.
[0060] In the event of a pressure surge from an adjacent flow
channel 152; 153 and therefore an increase in the pressure below
the tongue 181 in accordance with the illustration of FIG. 2, the
tongue closes the flow channel 151. This prevents a flow being
possible from one disconnection zone 1201; 1202; 1203 to another
disconnection zone 1201; 1202; 1203 of the poles 1101; 1102; 1103
of the electrical switch 1000.
[0061] FIG. 1 furthermore shows that the pressure trip unit 100
comprises a common collecting chamber 170 which is arranged between
the respective nonreturn valves 161; 162; 163 and the actuating
element 110.
[0062] This is illustrated in more detail in FIG. 3, in which a
flow through the flow channel 151 and through the nonreturn valve
161 located at the end thereof into the common collecting chamber
170 is illustrated. Owing to the increase in pressure in the common
collecting chamber 170, the actuating element 110 is deflected
upward in accordance with the illustration in FIG. 3 and actuates a
tripping lever of the switching lock of the multi-pole electrical
switch 1000.
[0063] The actuating element 110 can be designed as a tappet for
actuating a tripping lever of the switching lock. Furthermore, the
actuating element 110 can be provided with suitable structural
measures, for example with a spring, and can be held in its
inoperative position by the measure. In the event of a pressure
(p), the actuating element 110 can be actuated counter to the
spring force of the spring. As a result, for example, the response
behavior of the pressure trip unit 100 can be set by selection of
the spring.
[0064] The tongue 181 illustrated in FIG. 2 can be manufactured
from an electric-arc-resistant material, for example from aramid.
Aramid is a particularly temperature-resistant material which is
nevertheless flexible and pliant and permits the flection of the
tongue 181 from the inoperative position illustrated in FIG. 2 into
the deflected position illustrated by dashed lines. The response
behavior of the nonreturn valve 161 can be set by the material
thickness of the tongue 181. Similarly, the response behavior can
be set by the selection of the material of the tongue 181, on
account of the rigidity of the material.
[0065] Furthermore, the tongue 181 can be held between the first
housing part 191 and the second housing part 192 of the pressure
trip unit 100. The holding zone of the tongue 181 can have an angle
(.alpha.) and/or a bending radius which is formed in the first
housing part 191 or second housing part 192 and therefore
constitutes a prestressing of the tongue 181 for closing the flow
channel 151. The response behavior of the nonreturn valve 161 can
likewise be set with the variation of the angle (.alpha.) of the
holding zone of the tongue 181.
[0066] FIG. 5 illustrates a modularly constructed pressure trip
unit 100 according to an embodiment of the invention. This
comprises valve elements 141; 142; 143 having a respective
nonreturn valve 161; 162; 163 and a respective flow channel 151;
152; 153 (not included in the illustration of FIG. 5). Furthermore,
the pressure trip unit 100 illustrated in FIG. 5 comprises a
tripping element 147 for disconnecting the switching contacts 1211,
1221; 1212, 1222; 1213, 1223. For this purpose, the tripping
element 147 is provided with an actuating element 110, for example
a tappet. The valve elements 141; 142; 143 and the tripping element
147 are designed here so as to be able to be plugged together.
[0067] Furthermore, closing elements 145; 145' and connecting
elements 146 are provided for the mechanical construction of the
modular pressure trip unit 100. The closing elements 145; 145' and
the connecting elements 146 serve for the construction of a
pressure trip unit 100 according to an embodiment of the invention
which can be plugged together with the valve elements 141; 142; 143
and the tripping element 147.
[0068] An advantage of the modular pressure trip unit 100 is that
the latter is usable on electrical switches 1000 having a different
number of poles 1101; 1102; 1103 and is adaptable thereto. Higher
piece numbers of the individual elements, such as the valve
elements 141; 142; 143 permit cost-effective manufacturing. A
mechanical compensation for tolerances between the phases can
likewise be undertaken via the modular pressure trip unit 100.
[0069] The closing elements 145; 145', the connecting elements 146,
the valve elements 141; 142; 143 and the tripping element 147 can
be connected by way of laser beam welding, ultrasonic welding,
adhesive bonding or other joining methods in order to ensure as
great a gas tightness as possible.
[0070] In FIGS. 6A, 6B and 7 the electrical switch 1000 is
illustrated with a pressure trip unit 100 according to an
embodiment of the invention and a protective barrier 300. The
protective barrier 300 prevents the direct transport of particles
which are produced in the disconnection zone 1201; 1202; 1203 to
the pressure trip unit 100. The protective barrier 300 can be
composed of a material reinforced by aramid fibers or glass fibers
(e.g. aramid paper).
[0071] For this purpose, in accordance with the illustration in
FIGS. 6A and 6B, the protective barrier 300 is placed onto the flow
channel 151; 152; 153 and prevents direct transport of particles
which are produced in the disconnection zone 1201 to the pressure
trip unit 100.
[0072] The flow profile from the disconnection zone 1201 to the
pressure trip unit 100 is illustrated in FIG. 7. The flow passes
laterally around the protective barrier 300, and the gas can pass
through an opening in the protective barrier 300 into the flow
channel 151; 152; 153 and the pressure trip unit 100.
[0073] In FIGS. 8A, 8B and 9, the electrical switch 1000 is
illustrated with a pressure trip unit 100 according to an
embodiment of the invention and an alternative protective barrier
301. The alternative protective barrier 301 prevents the direct
transport of particles which are produced in the disconnection zone
1201; 1202; 1203 to the pressure trip unit 100.
[0074] For this purpose, in accordance with the illustration in
FIGS. 8A and 8B, the protective barrier 301 is held by the housing
of the electrical switch 1000 and prevents the direct transport of
particles which are produced in the disconnection zone 1201 to the
pressure trip unit 100.
[0075] The flow profile from the disconnection zone 1201 to the
pressure trip unit 100 is illustrated in FIG. 9. The flow passes
laterally around the protective barrier 301, and the gas enters the
flow channel 151; 152; 153 and the pressure trip unit 100.
[0076] In FIGS. 10A and 10B, the electrical switch 1000 is
illustrated with a pressure trip unit 100 according to an
embodiment of the invention and a further protective barrier 302.
The further protective barrier 302 prevents the direct transport of
particles which are produced in the disconnection zone 1201; 1202;
1203 to the pressure trip unit 100.
[0077] The pressure trip unit 100 according to an embodiment of the
invention is optimized for rapid tripping. The design is
constructed compactly, and therefore the paths for the pressure (p)
are kept short, which can ensure more rapid tripping. The pressure
trip unit 100 is produced as an assembly with integrated nonreturn
valves 161; 162; 163 at the interface with the pole cassette. A
tappet or actuating element 110 can bring the switching mechanism
to tripping.
[0078] The positive pressure arising in the event of a short
circuit in the pole shells is changed into mechanical force which
trips the switching mechanism of the electrical switch 1000.
[0079] The patent claims of the application are formulation
proposals without prejudice for obtaining more extensive patent
protection. The applicant reserves the right to claim even further
combinations of features previously disclosed only in the
description and/or drawings.
[0080] References back that are used in dependent claims indicate
the further embodiment of the subject matter of the main claim by
way of the features of the respective dependent claim; they should
not be understood as dispensing with obtaining independent
protection of the subject matter for the combinations of features
in the referred-back dependent claims. Furthermore, with regard to
interpreting the claims, where a feature is concretized in more
specific detail in a subordinate claim, it should be assumed that
such a restriction is not present in the respective preceding
claims.
[0081] Since the subject matter of the dependent claims in relation
to the prior art on the priority date may form separate and
independent inventions, the applicant reserves the right to make
them the subject matter of independent claims or divisional
declarations. They may furthermore also contain independent
inventions which have a configuration that is independent of the
subject matters of the preceding dependent claims.
[0082] None of the elements recited in the claims are intended to
be a means-plus-function element within the meaning of 35 U.S.C.
.sctn.112(f) unless an element is expressly recited using the
phrase "means for" or, in the case of a method claim, using the
phrases "operation for" or "step for."
[0083] Example embodiments being thus described, it will be obvious
that the same may be varied in many ways. Such variations are not
to be regarded as a departure from the spirit and scope of the
present invention, and all such modifications as would be obvious
to one skilled in the art are intended to be included within the
scope of the following claims.
* * * * *